Answer: Door-in-the-face technique
Explanation: This technique is well suited to extort what we need, and in order to get what we need, we first place a request that is much larger than our need, which is usually denied due to a large request. This negative response is usually such that there is no mention of its fulfilment and it is as if someone slammed the door on our face. Much like Jacob's father mocking Jacob's $ 50 claim.
But after that, to our much smaller request, an answer is usually positive, and then we actually get what we need from the beginning, like Jacob $ 20 for gasoline.
Interestingly, scientists claim that, for example, if our second request, much smaller than the first one, was made in isolation, without the first major request, it would not be fulfilled. In other words, if Jacob had immediately claimed $ 20 without first claiming $ 50, his father would not have given him $ 20, according to the scientist. So, the first big request seems to soften the one to whom we are making the request, then the second request will be fulfilled. So did Jacob, to get $ 20 he first asked for $ 50.
