I forgot to attach the photo before. please help

Part (i)

I'll use H in place of T to represent the heat of the object. That way there isn't a clash of variables lowercase t vs uppercase T.

The equation we're working with is updated to:

H(t) = 22 + a*2^(bt)

Plugging in t = 0 as the initial time value should lead to the temperature being H = 86 degrees Celsius.

So,

H(t) = 22 + a*2^(bt)

86 = 22 + a*2^(b*0)

86 = 22 + a*2^0

86 = 22 + a*1

86 = 22 + a

a+22 = 86

a = 86-22

a = 64

Part (ii)

We'll use the value of 'a' we found earlier. Plus we'll use the fact that H = 28 when t = 0.5 (since 30 min = 30/60 = 0.5 hr).

H(t) = 22 + a*2^(bt)

28 = 22 + 64*2^(b*0.5)

28-22 = 64*2^(0.5b)

64*2^(0.5b) = 6

2^6*2^(0.5b) = 6

2^(6+0.5b) = 6

log(  2^(6+0.5b)   ) = log(6)

(6+0.5b)*log(2) = log(6)

6+0.5b = log(6)/log(2)

6+0.5b = 2.5849625

0.5b = 2.5849625-6

0.5b = -3.4150375

b = -3.4150375/(0.5)

b = -6.830075

answer: the answer is one of

step-by-step explanation:   we are given to write a proper fraction where the whole is divided into an even number of equal parts less than ten, and an odd number of those parts exist.

an even number less than 10 may be one of 2, 4, 6 or 8. so, the whole may be one of these four evens.

now, an odd number of these parts must exist, so the numerator must be an odd number, one of 1, 3, 5 or 7. it cannot be 9 because then the fraction will become improper.

thus, our fraction may be one of the following