Answer:
7.83
Step-by-step explanation:
cos(40)=6/(ZX)
zx=7.83
Answer:
a) x = 5
b) x = 4
Step-by-step explanation:
a) x = 5
You can get this with a calculator if you need by using the log function.

x = 5
b) x = 4
According to the product rule of exponents: 
So, x + 11 = 15 --> x = 4
54+9= 63 m = distance and time=35 sec hence, speed= 63/35=9/5=1.8 m/s
time taken to reach water surface= distance/speed=54/1.8=30 sec
Answers:
a. -80
b. -60
c. 98
d. -54