Radio communication between distant places on Earth is possible because the
A) ionosphere reflects radio signals.
B) ionosphere transmits radio signals.
C) stratosphere reflects radio signals.
D) exosphere reflects radio signals.
Question 2
Which of statement below about black holes is not true?
A) Although we are not 100 certain that black holes exist, we have strong observational evidence in favor of their existence.
B) If you watch someone else fall into a black hole, you will never see him (or her) cross the event horizon; you'll only see him fade from view as the light he emits or reflects becomes more and more redshifted.
C) A spaceship passing near a 10-solar-mass black hole is much more likely to be destroyed than a spaceship passing at the same distance from the center of a 10-solar-mass main-sequence star.
D) If you fell into a black hole, you would experience time to be running normally as you plunged rapidly across the event horizon.
From space earth shows itself as a planet covered mostly by water.
The span of Homo sapiens sapiens’ time on earth
Earth and the Moon
Earth Affects People; People Change Earth
El Anatsui, Between Earth and Heaven.
Human Communication: The Basic Course, 14th Edition