Plz help me it’s rlly hard

Find the number of positive three-digit even integers whose digits are among 9, 8, 7,5, 3, and 1.

Is the square root of 4 plus the square root of 16 rational?

The u-drive rent-a-truck company plans to spend $13 million on 320 new vehicles. each commercial van will cost $25 comma 000, each small truck $50 comma 000, and each large truck  $80 comma 000. past experience shows that they need twice as many vans as small trucks. how many of each type of vehicle can they buy?