A. first one is your answer.
Answer:
10%
Step-by-step explanation:
The computation of the percentage of bulbs that switched on incandescent is as follows;
Let us assume the incandescent be I
And, the fluorescent be F
Now the equation is
0.4I + 0.9F = 0.8 (I+F)
0.41I + 0.9F = 0.8I + 0.8F
So here
0.4I = 0.1F
Now the percentage would be for incandescent in the case of switched on is
= 0.4I ÷ 0.8(I+F) × 100
= 0.1F ÷ 1F
= 10%
All of the statements has the qualifier "can be".
This means that we need just one single in each example to make the statement true.
In an equilateral triangle, medians, angle bisectors, altitudes and perpendicular bisectors are all coincident, which makes the first three statements true. This in turn makes the fourth statement true.
So there are no false statements.