Answer:
69.74 N
Explanation:
We are given that
Weight of sled=49 N
Coefficient of kinetic friction
Weight of person=585 N
Total weight==mg=49+585=634 N
We know that
Force needed to pull the sled across the snow at constant speed,F=Kinetic friction

Where N= Normal=mg

Hence, the force is needed to pull the sled across the snow at constant speed=69.74 N
Answer:
72.98 km
Explanation:
Her displacement is simply the distance from her final position to her initial position.
Now, I've drawn and attached a triangle diagram to depict this her movement.
Point O is her initial starting point.
Point A is the first point she gets to after travelling north while point B is the final point after travelling north east.
From the triangle, the displacement will be the distance OB which is denoted by x and can be solved from cosine rule.
Thus;
x² = 62² + 26² - 2(62 × 26)cos 120
x² = 4520 + 806
x² = 5326
x = √5326
x = 72.98 km
B. Earth’s outer surface is cooler than its interior layers.
Explanation:
- The option given above is showing us that the temperature in the interior of the earth is higher than the temperature in the outer layer.
- There is travel of heat from the inner core of the earth to the earth's crust. Due to the loss of heat when it reaches the outer layer, there arises a temperature difference.
- The heat loss is due to the absorption of heat during its transfer. Hence, option B is the answer.
Im guessing it's (a) since the numbers go in chronological order and you read the periodic table left to right