Please help me I have been stuck for a while

An appliance salesman sets a goal to sell an average of 6 appliances per day for the first two weeks of his new job. the dot plot shows the number he sold each day during the first 13 days. what is the minimum number of appliances he must sell on the 14th day in order to reach his goal? a) 5 b) 6 c) 7 d) 8

Plot a point at the y-intercept of the following function on the provided graph. 3y=-5x+7 20 points

Rose bought a new hat when she was on vacation. the following formula describes the percent sales tax rose paid b=t-c/c