Answer:
100°
Step-by-step explanation:
two angles are supplement .
if their sum is equal to 180°
supplement angle of 80° + x = 180°
180° - 80° = 100° answer
Markup means they sell it for that percentage more than they bought it for. First let's calculate how much they will mark it up for:

Convert 87% into a decimal(87/100):

Multiply:

This is how much they'll mark it up, now let's add it to how much they bought it for to find out the selling price:
Answer:
31.581 grams rounded to the nearest tenth is 31.6