哪个命令可以将所有已挂载文件系统的易读用量信息保存到 ~/project/disk_usage.txt？
~/project/disk_usage.txt
df -h < ~/project/disk_usage.txt
df -i > ~/project/disk_usage.txt
df -h > ~/project/disk_usage.txt
du -h > ~/project/disk_usage.txt