Human penis tension of the suspensory ligament that holds it in position. The following table shows how common various erection angles are for a standing male, out of a sample of 1,564 males aged 20 through 69. In the table, zero degrees is pointing straight up against the abdomen, 90 degrees is horizontal and pointing straight forward, while 180 degrees would be pointing straight down to the feet. An upward pointing angle is most common. Ejaculation is the ejecting of semen from the penis, and is usually accompanied by orgasm. A series of muscular contractions delivers semen, containing male gametes known as
Back-in angle parking in traffic delays and considerable risk of collisions with pedestrians, bicyclists, and vehicles. Existing pull-in angle parking spaces can be converted to back-in angle parking by re-striping to flip the angle of the stall markings. Streets with parallel parking have also been converted to back-in angle parking. In either case, the pavement markings are often augmented with signage indicating that vehicles must be backed in. According to the Pedestrian & Bicycle Information Center, back-in angle parking provides motorists with better vision of pedestrians, bicyclists, motor vehicles, and other road users as they exit a parking space and enter moving traffic.