Me ayudan no entiendo que debo hacer

What is the simplified form of 7 √x • 7 √x • 7 √x • 7 √x?

On average, how many more hits will he get when he bats 100 times at home during the day as opposed to 100 times away at night?

Aroulette wheel has 38 slots in which the ball can land. two of the slots are green, 18 are red, and 18 are black. the ball is equally likely to land in any slot. the roulette wheel is going to be spun twice, and the outcomes of the two spins are independent.the probability that it lands one time on red and another time on black in any order is(a) 0.5 (b) 0.25 (c) 0.4488 (d) 0.2244