210chairs since the ratio is 3/3 which is 1/1 since 7 carpenters make 7 chairs every day for 30 days thats 7 * 30 which is 210
to find the slope for the first one, use the formula 
(It's the slope formula)
so... 
then plug in... 
this line has a slope of 0
As for the miles problem, to find mph, the miles have to be at 1.
so... 
therefore, he drove 60.5 mph
2(3t - 1) - 5(t - 1)
2(3t) - 2(1) - 5(t) + 5(1)
6t - 2 - 5t + 5
6t - 5t - 2 + 5
t + 3