Answer:
Explanation:18kt alloy contains
i) 75% of gold
rhogold=19.3g/cm^3
=75/100×19.3
=14.475g/cm^3
ii) 16% of silver
rhosilver=10.5g/cm^3
=16/100×10.5
=1.68g/cm^3
iii) 9% of copper
rhocopper =8.90g/cm^3
=9/100×8.9
=0.801g/cm^3
Overall density of 18kt gold
=(0.801+1.68+14.475)g/cm^3
=16.956g/cm^3
=17g/cm^3 to 3s.f
A: geologist
b: physical science
c: space science
d: ecologist
Answer:
10.4 m/s
Explanation:
The problem can be solved by using the following SUVAT equation:

where
v is the final velocity
u is the initial velocity
a is the acceleration
t is the time
For the diver in the problem, we have:
is the initial velocity (positive because it is upward)
is the acceleration of gravity (negative because it is downward)
By substituting t = 1.7 s, we find the velocity when the diver reaches the water:

And the negative sign means that the direction is downward: so, the speed is 10.4 m/s.
1. In 2010-2011, the temperature decreased. In 2011-present, the temperature started increasing. From 390 to 405+
2. As the more carbon dioxide increases the temperature also increases with it.