Answer:
Step-by-step explanation:
Standard equation of an ellipse,
(h, k) is the center of the ellipse
Value of a = Distance of the center from the vertex
b = Distance of the center from the covertex
From the picture attached,
a = Distance of the center (h, k) from the vertex (2, -2) = 3 units
b = Distance of the center (h, k) from the co-vertex (-1, 0) = 1 unit
Center of the ellipse (h, k) = (-1, -2)
Answer:
B. 2.77 · 10^28
Step-by-step explanation:
The total number of atoms is ...
(6.02·10^23 atoms/mol)·(4.6·10^4 mol) = (6.02·4.6)·10^(23+4) atoms
≈ 27.7·10^27 atoms
≈ 2.77·10^28 atoms . . . . . . put in scientific notation form
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Scientific notation has one non-zero digit to the left of the decimal point and the exponent adjusted accordingly.
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Your calculator can help you figure this out. If necessary, put the display into scientific notation mode. (For numbers this size, it is usually not necessary.)
Answer:
6.75 hour is approximated to 7 hours
Step-by-step explanation:
Given
Time = 6.75 hours
Required
Round to the nearest hour
The time given is given in base 10 and the conversion can be done in two ways.
1. Convert directly by approximation.
Approximating 6.75 to the nearest whole number gives 7.
Hence, 6.75 hours = 7 hours
2. Convert to time equivalent then approximate time
This is done as follows
Convert decimal to fraction
Simplify to lowest term
Convert hour to minute
There are 60 minutes in an hour
The rule of time approximation is that; if the minutes is between 0 and 29, it'll be rounded to 0; else, it'll be rounded up to 1
Going by the rule, 45 minutes will be approximated to 1 hour.
This gives
Hence, 6.75 hour is approximated to 7 hours