2 A particle \(P\) is projected vertically upwards with speed \(25 \mathrm {~m} \mathrm {~s} ^ { - 1 }\) from a point 3 m above horizontal ground.
- Find the time taken for \(P\) to reach its greatest height.
- Find the length of time for which \(P\) is higher than 23 m above the ground.
- \(P\) is higher than \(h \mathrm {~m}\) above the ground for 1 second. Find \(h\).