There are 2 answers: Choice 1, Choice 4
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Why is this? Because we use the rule
P(A & B) = P(A) * P(B)
which only works if events A and B are independent
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For the first answer choice,
P(A) * P(B) = 0.6*0.4 = 0.24 = P(A & B)
so that matches.
The same applies to the fourth answer choice as well
P(A) * P(B) = 0.3*0.2= 0.06 = P(A & B)
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The other answer choices don't match up.
The second answer choice has
P(A) * P(B) = 0.3*0.4 = 0.12 but that doesn't match with the 0.70 given
Similarly for the third answer choice,
P(A) * P(B) = 0.5*0.1 = 0.05 which doesn't match with the 0.60
Answer:
3.15 seconds is the answer.
<u>Explanation</u>
when the ball touches the ground, h =0
hence,
0=255-21t-16t²
16t²+21t-225=0
here a=16 ,b=21, c= -225

time cannot be negative, hence t = -4.46 can be avoided
The ball takes 3.15 seconds to hit the ground.
Vertex: (1,-4)
axis of symmetry: x=1
min
minimum value: y=-4
x intercepts: -1, 3
y intercept: -3
i dont know how to find solutions or roots sorry
S=k and a=4s-2, replacing s with k in a gives you:
a=4k-2