Answer:
145 hours
Explanation:
Since one hour of riding a bicycle takes up 505 kcal of energy. It is also stated that one gram of body fat is equal to 7.70 kcal. Also, it is given that 1 pound of body fat is equal to 454 g.
Hence;
1 Ib= 454 g
21 Ib= 21 × 454/1 = 9534 g
But
1g of body fat = 7.70kcal
9534 g of body fat = 9534 × 7.70 kcal/1 = 73411.8 kcal
If 505 kcal is lost in 1 hour
73411.8 kcal is lost in 73411.8 kcal × 1hour/505k cal = 145 hours
Answer: chemical weathering
Explanation: Chemical weathering is different from mechanical weathering because the rock changes, not just in size of pieces, but in composition. That is, one type of mineral changes into a different mineral. Chemical weathering works through chemical reactions that cause changes in the minerals.
Answer is: <span>molecular formula of retinol is C</span>₂₀H₃₀O.
n(C) = 83,84 g ÷ 12 g/mol.
n(C) = 6,99 mol.
n(H) = 10,58 ÷ 1,008 g/mol.
n(H) = 10,5 mol.
n(O) = 5,58 g ÷ 16 g/mol.
n(O) = 0,348 mol.
n(C) : n(H) : n(O) = 6,99 mol : 10,5 mol : 0,348 mol /:0,348.
n(C) : n(H) : n(O) = 20 mol : 30,1 mol : 1.
It's changing a thing with force, not chemicals, like cutting paper
Physical changes can affect physical properties.
Hoped this helped.
~Bob Ross®
