Question

please check my answer i think its a

Answer 1

sorry i think its D

Answer 2

Rate at which Frank can type=1/6
Rate at which James can type= 1/7
\[\frac{ 1 }{ 6 }+\frac{ 1 }{ 7 }=T\] T=time it take for both of them to type together.

Answer 3

so it would have to be A?

Answer 4

yup