The angle of elevation of a ladder leaning against a wall is $45^{\circ},$ and the foot of the ladder is $4.242 \ m$ away from the wall. The length of the ladder is (in $m$):

$A$ man is standing near a $6 \, m$ long pole which casts an $8 \, m$ long shadow. If the man casts a shadow of $2.4 \, m$,what is the height of the man (in $m$)?

$A$ tower stands on a horizontal plane. $A$ man on the ground $100 \ m$ from the base of the tower finds the angle of elevation of the top of the tower to be $30^{\circ}$. What is the height of the tower (in $m$)?

The angle of elevation of an aeroplane as observed from a point $30 \ m$ above the transparent water surface of a lake is $30^{\circ}$ and the angle of depression of the image of the aeroplane in the water of the lake is $60^{\circ}$. The height of the aeroplane from the water surface of the lake is (in $m$):

$A$ tower stands at the end of a straight road. The angles of elevation of the top of the tower from two points on the road $500 \ m$ apart are $45^{\circ}$ and $60^{\circ},$ respectively. Find the height of the tower.

Two poles of height $7 \ m$ and $12 \ m$ stand on a plane ground. If the distance between their feet is $12 \ m$,the distance between their tops will be (in $m$):