I need help ASAP my friends so please help me :-)

What is the length of the missing leg in this right triangle? 18 mm 24 mm 26 mm 32 mm

Simplify the expression. -2/5(10+15m-20n)

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?