What is the value of this expression when a equals 7 and b= -4

Assume that a population of 50 individuals has the following numbers of genotypes for a gene with two alleles, b and b: bb = 30, bb = 10, and bb = 10. calculate the frequencies of the two alleles in the population’s gene pool.

In which figure is de bc ? a. figure 1 b. figure 2 c. figure 3 d. figure 4

15m is what percent of 60m; 3m; 30m; 1.5 km? the last one is km not m