The depth of water, in metres, at a certain point in a harbour varies with the tide and can be modelled by a function of the form f(t) = a + bcosct
where t is the time in hours from the first high tide on a particular Saturday and a, b, and c are constants. (Note: ct is expressed in radians.)

On that Saturday, the following were noted:
The depth of the water in the harbour at high tide was 5.5 m
The depth of the water in the harbour at low tide was 1.7 m
• High tide occurred at 02:00 and again at 14:34.

Find the values of a and b

answer: 2 and 1

step-by-step explanation: got this question

0.16 or 16%

step-by-step explanation:

lets take a coin for example.

if you toss it twice, it has a 1/4 chance of landing on heads both times because 1/2 * 1/2 is 1/4.

with the cards, the chance of picking dog is 0.4. having two people pick one is like picking a card twice in a row. so 0.4 * 0.4 is 0.16, or 16%

first, we define the variables:

x: number of years after 1950

f (x): amount of vinyl sold.

then, with the variables defined, we have:

68594 vinyl records were sold in 1958 > f (8) = 68594

91299 vinyl records were sold in 1961 > f (11) = 91299

38720 vinyl records were sold in 1952 > f (2) = 38720

161743 vinyl records were sold in 1967 > f (17) = 161743

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step-by-step explanation:

slope is 35 and 20 miles is the y-intercept.

step-by-step explanation: