Answer:
2
Step-by-step explanation:
Answer:
0
Step-by-step explanation:
If you think in degrees easier than in radians, then make this conversion.
pi = 180 degrees
(3/2)*pi = (3/2) * 180 = 180 * 3/2 = 270
Sin(270) = -1
cos(270) = 0
==========
sin(270) * cos(270) = -1 * 0 = 0
Answer:
23.1 hours
Step-by-step explanation:
the mean is calculated as
mean = ∑ fx ÷ ∑ f
where x is the midpoint of the time intervals
0 < h ≤ 10 ⇒ x = 5
10 < h ≤ 20 ⇒ x = 15
20 < h ≤ 30 ⇒ x = 25
30 < h ≤ 40 ⇒ x = 35
then
∑ fx = (5 × 5) + (15 × 15) + (50 × 25) + (10 × 35)
= 25 + 225 + 1250 + 350
= 1850
∑ f = 5 + 15 + 50 + 10 = 80
then
mean = 1850 ÷ 80 ≈ 23.1 hours (to 1 dp )
Using th epythagorean theorem.
52^2-48^2= x^2
2704-2304= x^2
400=x^2
x=20
Final answer: D