Established bands made something of a comeback in the mid-1980s. After an 8-year separation, Deep Purple returned with the classic Machine Head line-up to produce Perfect Strangers (1984), which reached number five in the UK, hit the top five in five other countries, and was a platinum-seller in the US. After somewhat slower sales of its fourth album, Fair Warning, Van Halen rebounded with the Top 3 album Diver Down in 1982, then reached their commercial pinnacle with 1984. It reached number two on the Billboard album chart and provided the track "Jump", which reached number one on the singles chart and remained there for several weeks. Heart, after floundering during the first half of the decade, made a comeback with their eponymous ninth studio album which hit number one and contained four Top 10 singles including their first number one hit. The new medium of video channels was used with considerable success by bands formed in previous decades. Among the first were ZZ Top, who mixed hard blues rock with new wave music to produce a series of highly successful singles, beginning with "Gimme All Your Lovin'" (1983), which helped their albums Eliminator (1983) and Afterburner (1985) achieve diamond and multi-platinum status respectively. Others found renewed success in the singles charts with power ballads, including REO Speedwagon with "Keep on Loving You" (1980) and "Can't Fight This Feeling" (1984), Journey with "Don't Stop Believin'" (1981) and "Open Arms" (1982), Foreigner's "I Want to Know What Love Is", Scorpions' "Still Loving You" (both from 1984), Heart's "What About Love" (1985) and "These Dreams" (1986), and Boston's "Amanda" (1986).

Answer this question, if possible (if impossible, reply "unanswerable"): Which Heart album contained 10 number one hits?
unanswerable