It's a little hard to read, but I think I can help you.
a) (2^9*2^11*2^3)/(2^7)^3
(2^(9+11+3))/(2^(7*3)) Remember (a^b)^c=a^(b*c) and a^b*a^c=a^(b+c)
2^23/2^21
2^(23-21) <- Exponents with the same base when divided get subtracted
2^2
4 is the answer
b) ((0.4^2)^10)/(0.4^9*0.4^7*0.4)
0.4^(2*10)/0.4^(9+7+1)
0.4^20/0.4^17
0.4^3
0.064 is the answer
