DN A chemical substance has a decay rate of 8.1% per day. The rate of change of an amount of the chemical after t days is given by
dt
= -0.081N.
a) Let No represent the amount of the substance present at t = 0. Find the exponential function that models the decay.
b) Suppose that 700 g of the substance is present at t = 0. How much will remain after 2 days?
c) What is the rate of change of the amount of the substance after 2 days?
d) After how many days will half of the original 700 g of the substance remain?
.
a) N(t) - No e -0.0810
b) After 2 days, I will remain.
(Round to the nearest whole number as needed.)

Answer: d. 39 cmin the diagram, the approximate length of the minor arc de is 39 centimetres.step-by-step explanation: the formula for the length of an arc in a circle is as displayed below.let the length of the minor arc de = xx = 2( pi )r × angle of sector / 360°from this, we will substitute the values given from the problem into the formula to obtain the length of the minor arc de.x = 2( pi )r × angle of sector / 360°r = radius = 25cmpi as an approximate value = 3.14angle of sector = 120°x = 2( 3.14 )( 25 ) × 120° / 360°x = 157 × 1 / 4x = 39.25x = 39 ( rounded to the nearest whole number as an approximate value )