This response to singer is a little technical, but the author gives a succinct breakdown of his main argument, which you will be asked to recapitulate if you write about him on the test.

"Singer's argument for our obligation to assist can be stated very simply:

... if it is in our power to prevent something bad from happening, without thereby sacrificing anything of comparable moral importance, we ought, morally, to do it. Since it is in our power to prevent people from starving to death without sacrificing anything of comparable moral importance, we ought, morally, to do it. Therefore we have a moral obligation to give as much to the starving as we can do without reducing ourselves to a comparable level of poverty. (Singer 1993, p. 231)

As it stands, this argument is somewhat ambiguous. We can begin to deal with the ambiguities by making its structure a little more formal;

P1. If it is in our power, by performing action A, to prevent some bad event E from happening, and we can prevent his bad event E from happening without causing an event E' which is morally at least as bad as E, then we ought to perform action A.

P2. It is in our power, by donating money to overseas aid, to prevent people from starving to death, and we can prevent people from starving to death without causing an event which is morally at least as bad as allowing people to starve to death.

Therefore;

We ought to donate money to overseas aid."

From Singer's article What Should a Billionaire Give – and What Should You?

"More important than questions about motives are questions about whether there is an obligation for the rich to give, and if so, how much they should give. A few years ago, an African-American cabdriver taking me to the Inter-American Development Bank in Washington asked me if I worked at the bank. I told him I did not but was speaking at a conference on development and aid. He then assumed that I was an economist, but when I said no, my training was in philosophy, he asked me if I thought the U.S. should give foreign aid. When I answered affirmatively, he replied that the government shouldn’t tax people in order to give their money to others. That, he thought, was robbery. When I asked if he believed that the rich should voluntarily donate some of what they earn to the poor, he said that if someone had worked for his money, he wasn’t going to tell him what to do with it.

At that point we reached our destination. Had the journey continued, I might have tried to persuade him that people can earn large amounts only when they live under favorable social circumstances, and that they don’t create those circumstances by themselves. I could have quoted Warren Buffett’s acknowledgment that society is responsible for much of his wealth. “If you stick me down in the middle of Bangladesh or Peru,” he said, “you’ll find out how much this talent is going to produce in the wrong kind of soil.” The Nobel Prize-winning economist and social scientist Herbert Simon estimated that “social capital” is responsible for at least 90 percent of what people earn in wealthy societies like those of the United States or northwestern Europe. By social capital Simon meant not only natural resources but, more important, the technology and organizational skills in the community, and the presence of good government. These are the foundation on which the rich can begin their work. “On moral grounds,” Simon added, “we could argue for a flat income tax of 90 percent.” Simon was not, of course, advocating so steep a rate of tax, for he was well aware of disincentive effects. But his estimate does undermine the argument that the rich are entitled to keep their wealth because it is all a result of their hard work. If Simon is right, that is true of at most 10 percent of it."