Answer:
65.94
Step-by-step explanation:
Answer:
1) 
2) 
Step-by-step explanation:
You can convert he mixed numbers to improper fractions:
1. Multiply the whole number part by the denominator of the fraction.
2. Add the product obtained to the numerator.
3. The denominator does not change.
Then:

Observe that, in each subtraction, the denominators are equal, then you can rewrite the denominator and subtract the numerators:

Divide 15 by 4. The quotient will be 3 and the remainder 3.
Then:

Answer:
2 km
Step-by-step explanation:
4π = π × r²
r² = 4
r = 2
Answer:
Condition 1: y>0
Condition 2: x+y>-2
Step-by-step explanation:
We are told that we have a set of points in the Cartesian system (i.e. x-y coordinate), so we can define our point as:

We are given two conditions and we want to create a system of inequalities. Now, generally speaking, inequalities are expressions relating mathematical expressions through 'comparison' (i.e. less than, greater than, or less/greater and equal to) usually recognized by
,
,
and
, respectively.
So in our case let set up our inequalities.
Condition 1: the y-coordinate is positive
This can be mathematically translated as
(i.e.
is greater than 0, therefore positive)
Condition 2: the sum of the coordinates is more than -2
This can be mathematically translated as

(i.e. the summation of the two coordinates is greater than -2 but not equal to).
The system of inequalities described by the two conditions is:

Frequency is the Number of Waves passing through a Point in One Second
Given : The Frequency of the Wave is : 700 Hz
Given : The Wavelength of the Wave is : 6 meter
⇒ In One second 700 waves of Wavelength 6 meter cross the point
⇒ In One second the First wave travels : 700 × 6 meters
⇒ In One second the First wave travels : 4200 meter
⇒ The Speed of the wave is : 4200 m/sec