Answer:
145 m
Explanation:
Given:
Wavelength (λ) = 2.9 m
we know,
c = f × λ
where,
c = speed of light ; 3.0 x 10⁸ m/s
f = frequency
thus,

substituting the values in the equation we get,

f = 1.03 x 10⁸Hz
Now,
The time period (T) = 
or
T =
= 9.6 x 10⁻⁹ seconds
thus,
the time interval of one pulse = 100T = 9.6 x 10⁻⁷ s
Time between pulses = (100T×10) = 9.6 x 10⁻⁶ s
Now,
For radar to detect the object the pulse must hit the object and come back to the detector.
Hence, the shortest distance will be half the distance travelled by the pulse back and forth.
Distance = speed × time = 3 x 10^8 m/s × 9.6 x 10⁻⁷ s) = 290 m {Back and forth}
Thus, the minimum distance to target =
= 145 m
1) D
2) I would say A, but not 100%, its the only one that makes sense tho
Since, A is a vector. Hence, we can break it into two components (x and y)
Angle made by the velocity vector A with the x-axis = 51.7°
Magnitude of the vector A = 70 m/s
°

m/s
°

m/s
Hence, the option C is correct.
1. Monophly - all descendants of an ancestral talon are grouped together (i.e. phylogenetic analysis should clearly demonstrate both monophyly and validity as a separate lineage).
2. Reasonable - with respect to evolutionary relevant criteria, i.e ecology morphology, or biogeography; DNA sequences are a consequence rather than a condition of divering evolutionary lineages
I believe it would be, if I have calculated correctly, 25 degrees C.