Answer:
Number of bulbs which can be lit using 1 kg of coal = 9
Step-by-step explanation:
Energy yielded by burning 1 kg of coal = 30 × 106 joules
= 3180 joules
Amount of energy that can be used for electricity = 30 % of 3180 joules
= 0.30 × 3180
= 954 joules
Energy needed for lighting one bulb = Wattage of bulb × No. of hours of lighting
⇒ Energy needed for lighting one bulb = 100 × 1
= 100 joules

Hence, Number of bulbs which can be lit using 1 kg of coal = 9
Answer:
I'm guessing 3 or 2
Step-by-step explanation:
3 or 2 because you can't have 2 and I would equal 8 which would also equal 3x +2y
Answer:
DEF is 90° because it is a right angle
Answer:
D.
Explanation
We know that g(x) = f(1/2x)
Additionally, the graph of f(x) passes through the point (-2, 0) and (2, 0).
It means that f(-2) = 0 and f(2) = 0
Then, g(-4) = 0 and g(4) = 0 because

Therefore, the graph of g(x) will pass through the points (-4, 0) and (4, 0). Since option D. satisfies this condition, the answer is graph D.
Answer:
(-1)/28
Step-by-step explanation:
Simplify the following:
((-19)/2×1/38)/7
(-19)/2×1/38 = (-19)/(2×38):
((-19)/(2×38))/7
(-19)/(2×38)×1/7 = (-19)/(2×38×7):
(-19)/(2×38×7)
The gcd of -19 and 38 is 19, so (-19)/(2×38×7) = (19 (-1))/(2 (19×2) 7) = 19/19×(-1)/(2×2×7) = (-1)/(2×2×7):
(-1)/(2×2×7)
2×2 = 4:
(-1)/(4×7)
4×7 = 28:
Answer: (-1)/28