Question: What song on the album No Protection was a No. 1 in the "Billboard" Hot 100 in April 1987?

The "Billboard" Hot 100 is a chart that ranks the best-performing singles of the United States.  Its data, published by "Billboard" magazine and compiled by Nielsen SoundScan, is based collectively on each single's weekly physical and digital sales, as well as airplay and streaming.  At the end of a year, "Billboard" will publish an annual list of the 100 most successful songs throughout that year on the Hot 100 chart based on the information.  For 2005, the list was published on December 20, calculated with data from December 4, 2004 to November 26, 2005.  The R&B track We Belong Together by American singer Mariah Carey was named the number 1 song of 2005 and it spent the longest time at number 1 for the year, 14 weeks.  This is also the joint-second longest time at number 1 for a single in the 57-year history of the Hot 100 post-1958 inception, after Mariah Carey's own collaboration with Boyz II Men, One Sweet Day, which spent 16 weeks atop the Hot 100 from 1995 to 1996. <SEP> No Protection (1987) is the second album by Starship.  This was the last album to be produced for Grunt Records, and the final Starship album to feature Grace Slick on vocals; she left Starship in 1988 and rejoined Jefferson Airplane for their reunion tour and self-titled reunion album, "Jefferson Airplane" in 1989.  The album featured the hit single "Nothing's Gonna Stop Us Now", and the Top 10 hit "It's Not Over ('Til It's Over)", the former of which was included on the soundtrack of the fantasy comedy movie "Mannequin" and the latter of which was a tune originally performed the previous year by one-time Manfred Mann's Earth Band frontman Chris Thompson for "Playing for Keeps" soundtrack.  The Diane Warren-penned ballad "Set the Night to Music" would become a hit four years later in 1991, as a duet between R&B legend Roberta Flack and reggae singer Maxi Priest, as released from Flack's album "Set the Night to Music". <SEP> "Nothing's Gonna Stop Us Now" is a 1987 song co-written by Albert Hammond and Diane Warren, recorded by the American rock band Starship in 1986.  It is a duet featuring Starship vocalists Grace Slick and Mickey Thomas.  Featured as the theme to the romantic comedy film "Mannequin", it hit No. 1 in the "Billboard" Hot 100 on April 4, 1987 and reached No. 1 on the UK Singles Chart for four weeks the following month and became the UK's 2nd biggest selling single of 1987.  The song also reached the top 10 in six European countries.  The single became the first number one single by songwriter Diane Warren.  At the time, it made Grace Slick (aged 47) the oldest woman to have a number one single in the United States though the record was later broken by Cher's "Believe" in 1999 (aged 52). <SEP> "Something So Strong" is a rock song written by Neil Finn and Mitchell Froom and performed by the band Crowded House for their eponymous debut album (June 1986).  The track was released as the album's fifth and final single in April 1987.  The single peaked at No. 18 on the Australian Kent Music Report Singles Chart, No. 3 in New Zealand, No. 7 in the United States "Billboard" Hot 100, and No. 10 on the Canadian "RPM" 100.