Step-by-step explanation:
The number of subsets=2ⁿ where n=4 members
2ⁿ=2⁴=16
Number of proper subsets=2ⁿ-1
16-1=15
Answer:
4 days a week
2+1=3
3+1/2+12=4
Not sure, It's getting kinda annoying ngl