Answer:
Step-by-step explanation:
so they used a total of 560 units
we are next told that if the units of usage are 360 or less use the 1st formula, but there is morn than 360 units in the given amount so use the 2nd formula
0.1(x-360+54)
0.1(560-360) + 54 = monthly bill
20+54 = monthly bill
74 = monthly bill
answer D looks good