so 1. 10 minus 5 and 1/2 = 4 and 1/2 divide by 3 and get 1 and 1/2 or 3/2 per day
2. there is no graph provided so I cannot solve this part
3. 650-x(50)>75 575-x(50)>0 50(11.5-x)>0 x must be less than 11
4. first is total cost=0.25m+5
second is total cost=50 so we put total cost of second less than first so 50>0.25m+5 45>0.25m 180>m so you can talk less than 180 minutes to spend less than the first option