The algebraic expression 4x^2+3 sqrt+5 is a polynomial

Factorize: x^2+8x+10 i just solved it but i don't know if the process is correct

Successful implementation of a new system is based on three independent modules. module 1 works properly with probability 0.96. for modules 2 and 3, these probabilities equal 0.95 and 0.90. compute the probability that at least one of these three modules fails to work properly.

Find the number of liters in 12.8 gal of gasoline. round to the nearest hundredths