To Earn Income
To Make Money
Because the hiragana ends with an う sound, you know this word is a verb. The kanji itself means earnings and the verb vocab version is to earn income, because you can't "to income" something. Can also be to make money.
かせぐ
You earn your income, and every time you're paid, you're given your money in a briefcase (かせ). Imagine getting your income from a briefcase, opening it up, and grabbing the money from within. Then, you have to give the briefcase back at the specified dropoff.
現職の大統領が、前大統領よりもどれだけ多くのお金を稼いでいるか知っているかい？
Do you know how much more money the incumbent president earns than the former president?