Answer:
927.0 cm²
Step-by-step explanation:
Step 1: find Z
m < Z = 180 - (28 + 118) (sum of ∆)
= 180 - 146
Z = 34°
Step 2: Find side XY using the law of sines

Cross multiply


Divide both sides by 0.469


XY ≈ 50 cm
Step 3: find the area.
Area of ∆ = ½*XY*YZ*sin(Y)
XY ≈ 50 cm
= ½*50*42*sin(118)
= 25*42*0.8829
Area = 927.045
Area ≈ 927.0 cm² (nearest tenth)
we are given
The water level in Ricky lake changes at an average of -7/48 inch for 1 year
It means that
In 1 year , the water level changes at 
and we have to find the water level change after 5 years
so, we can multiply both sides by 5
In 5*1 year , the water level changes at 
In 5 years , the water level changes at 
Hence,
the water level change after 5 years is
........Answer
(a) d=days C=cost
d C
1 30
2 40
3 50
4 60
C=10(d-1)+30
(b) C=10(5-1)+30
C=40+30
C=70