The first one is x square +5x-4
The second one is (x-2)(x-8)
Answer:
(i) Approximately 3 half lifes
(ii) 
Step-by-step explanation:
(i) ∵ The half life of Radon-222 is approximately 3.8 days,
So, the number of half life in 11.46 days =
≈ 3
(ii) Since, the half life formula is,

Where,
= initial quantity,
t = number of periods
= half life of the quantity,
Given,
N = 
t = 11.46 days,



About 296 students are still in the school. but technically, all 368 students are still attending a school, just not the same one.
Attached solution with work.
Answer:
B. 10.9
Step-by-step explanation:
Area of triangle= 1/2*24*h
∠N=90° ⇒ Area of triangle= 1/2*MN*ON
MN²= h²+(24-7)²
ON²= h²+7²
- 24h=MN*ON
- 24h= √h²+(24-7)²*√h²+7²
- (24h)²=(h²+17²)(h²+7²)
- 576k=k²+289k+49k+289*49
- k²-238k+14161=0